Apparatus for making inner tubes



July 25, 1944. H, D. STEVENS 2,354,432

APPARALI'US. FOR MAKING INNER TUBES Orignl Filed Nov. 28, 1939 2 Sheets-Sheet 1 mimi ATTORNEYS 2 Sheets-Sheet` 2 IIIIIII 'III H. D. sTEvE'Ns APPARATUS FOR MAKING NNER TUBES Qriginal Filed Nov. 28 1939 July 25,` 1944.

INVENTOR @y @E ATTORNEYS /III IIIIII l l \\\\\\\\\\K\\\\\\\\\\\\\\\\\\ Patented July 25, 1944 y I f-.IAPPARATUS FORMAKING INNER TUBES 'I Horace D. Stevens, Mii-on, Ohio, assignor to The Firestone' Tire & Rubber Company,- Akron, Ohio, a` corporation fof Orhhio i i 7 original application Noventa-28,1939, serial No. 306,514. Divided-*and this application July-26,

1941, serial No. 404,191' h claims` (01.154549) This invention relates to apparatus `for Vthe manufacture ofinner-tubes for pneumatic'rtires,

and mored especially it relates to improved machines for. forming apertures in endlessunvulcaniaed inner tubestructures of the leak-proof type, andvformountingvalve stems on therespectiyeinner tubesover said apertures.

'1he application 4is a division of my prior ape plication forUnited States Letters Patent Serial Nog., \3Q6 ',5f1 4,v ,ledNovernber 28, 1939, now .Herent No. 2,272,895, issued February 10', 1942.

Inner tubes of thecharacter mentioned have 'theirinteriors coated with a ,viscouscomposition 'that-seals the lminute pores in the rubberand thusepre'vents seepage of air therethrough. In` the manuiacture of such tubes, a determinate. quantity ofthe Viscous composition is spewedinto a length of unvulcanized rubber tubing, after which,v the V,ends ,ofthe tubing are spliced together toprovide an endless tube structure. The

l-atteruisrthen rolleduorpressed progressively inr a .long itudinal direction to effect a uniform distributienet `the sealing composition throughout the interior of the tube. Thereafter thetube requires to be apertured to provide the necessary.

port over which thai/alize; stemis mountedto enable inflation; and deiiation ofthe tube.r Heretofore considerable difcultyhas been encoun-f tered in aperturing .the tube clue to the necessity of separatingthe Wallsythereof so that in perforating one wall of the "tube, the Vopposite side or wall will not bedarnaged,y and it is to the.

solution o f this problem that this invention primarily is-directed.y

vide an improved apparatus for aperturing the wallof anlunvulcanized inner tube structure; to avoid the possibilityr of4 damaging the wall ofthe tube opposite'the aperture Iduring the forming off the latter; to impart a slight tension to a local region of the tube vwhilean aperture is being formed in said region; toefect the separation of the tube walls in a local vregion thereof as an aperture is formed in said region; and to provide for disposition of Athesliigs cut, from the tubes in the forming of aperturestherein. Other objects. will be manifest as the-description proceeds.

Of the accompanying drawings:

Figure l is a side elevation of apparatusem-A bodying the principles of the, invention;

Figure 2 is a plan viewthereofv; Y .Figure 3 is a fragmentaryfro-nt elevation of the apparatus, andthe worktherein;

The chier" objects of the invention are to pro-l 1 Figure l isa vertical section through. they aperf 55 ture forming spindle of th'ejapparatus,' .and the Work, on a larger scale in inoperative position,v as viewed substantially on` the line 4v-*1 4 ofV .Figure 1; and` f.,

Fig-ure 5 is a fragrnrentar-y section of `the parts shown inligure 4, in operative engagement with the work. i

Before an inner tube is ready;y for ,treatment in the apparatus of the inventionfcertain preparatory operations are necessary beginning `with the placing of the viscous sealing or. proofing composition Withinthelength of tubing' as previously explained. At such time la r blast ofair is directed into the end of the tube, so that when the tube is spliced immediateiythereafter; somev of the air is entrapped `and confined Within the tube. The air, of course, remains" in the tube during the rolling operation .that distributes the proofing composition throughout the interior of the tube and presses'it toflattened condition, in which conditionit is presf'ted'tol the loperator of the apparatusV that -aperture'stl'egtube and,

Through the agency" of the' apparatus, the op' erator first applies suctiont alocalzone of the bottom wall orply ofthe tubein the -regionof the blister, to produce av downwardly extending recess or reentrantf' in thebottomwall of the tube. The presencev of Y air in the tube at this pointrassuresV that only thevbottom 'wall of the tube will have the recessorlreentrant formed therein. With the tube so held-,the apparatus next effects a slighttensioning of the upper Vvvall of the tube, over the lrecess in the bottom wall,

after VWhich a ru1ar--b1ank--is ,cutY fromY` the upper wall ofthe tube, directly over said recess and reentrant,the presenceofthe latter preventv ing'the Apossibilityrof damage glio. thelower ply of the tube by the cutting;instrumentality.' The slight tensioninthe region o f; the tube that lis loe-1 ing apertured facilitates the cuttinggof theblank from the tube. Soon'v as ity-isf, severed from the tube structurer the blank isfsucked into the cutting mechanism, and subsequently is ejected therefrom by air under pressure. As soon as the cutting mechanism is removed from the tube, the latter is moved so that the aperture just formed is in axial alignment with a vertically movable head that carriesa rubber valvestem. The depressing of said headv applies the base langeof the valve stem to the tube structure over the 'aperture therein, the head releasing the valve stem as it rises. This completes the cycle of opvulcanizing operation.

Figures 1 and 2, the apparatus' 'comprises a bed plate I that is mounted upon a suitable sup- :.front to rear thereof. w, eration and the tube is ready for the subsequenty i.

24 the duct 25 terminates in a counterbore, and seated in the latter is a perforated screen or disc 21 that is provided with an axial stem 28 that extends downwardly through the vertical portion of duct 25 and through a bore 29 of smaller size than said ductin vertical extension thereof. The lower end of the stem 29 extends vinto a slot 30 in the bottom face of the block, extending from The table 2| is formed `with a countersunk aperture 3|, that is in axial alignment with the vertical portion of duct 25 and is somewhat smaller than the counterbore at Lthe top thereof. The thickness of the disc 21 is leslsthan the depth of said counterbore so that it: may have limited axial movement, upon occavsion as desired. Angular movement of the arm f 3221s limited by adjustable stop-members 32, 32 that are threaded through the respective spacer porting structure (not shown) of proper height to: f

position the apparatus for convenient manual operation.` Preferably `the supporting structure is positioned beside a conveyor II, Figure 3, uponv blocks `I2 disposed at opposite corners of the front margin of the bed plate andthe blocks' I3 disposed somewhat to the rear thereof, at opposite sides of the plate. Supported'upon the spacer blocks I2 isfa supporting plate I4 that is of the same width as the said spacer blocks. Supported at its front margin upon the spacer blocks I3 is a relatively large plate I5, which plate is supported at its rear by any suitable means (not shown).

Carried upon Athesupporting plate I4 and the front marginal portion of plate I5 are dual frames Il, I3, which frames are of substantially similar construction and are arranged side by side, each frame having a forwardly 'extending portion that overhangs the supporting plate I4. The frame Il carries vthe mechanism lthat is provided for forming an aperture in an endless inner tube, andthe frame I8 `carries the mechanism that applies avalvelstemio the inner tube over lthe aperture formed therein. Anrunvulcanized inner tube" to befapertured `and to have a valve stem applied thereto is shown at r2l), and during the successive' operations Yof being apertured and re-l ceiving a valve stemsaid innertube `is supported upon a table 2I, disposed beneathy the aperturing and valve applying mechanisms. ySaid table requiresto be movable in its own plane through an arc of limited extent so that a determinate region thereof maybe positioned, in alternation, in alignment with 'the aperturing mechanism and with the valve'applying mechanism, and to this end said table is mounted upon the free end of an arm 22 that restsiupon the bed plate I0 beneath the plates I4, I5, the rearend of arm 22 being pivotauy attached to the bed plate at 23,',the

forward end of said 'arm extending beyond the front margin of the 'bed plate. Mounted upon the free end of the arm 22,"betweenthe latter andthe table 2l, isa suction terminal block 24 A portion-of the bed plate I0 "extends later# blocks I2 and extend into the arc of movement of said arm.

The arrangement is such that when the countersunk aperture 3I is overlaid by an inner tube on table 2|, suction applied through the pipe 25 andduct 25 will draw the' adjacent wall of the tube 20 into the countersunk aperture, thus forming a recess or reentrantv in the tube-wall, as is shown in Figure 5. The presence of the blister or air bubble in the tube above theaperture 3I efectually prevents the uppermost ply of the tube wall from being drawn into' vcontact with thev lower ply thereof. Slidably mounted inl slot of block 24 is an adjustment slide 33 that is so shaped as to lift the disc 21 from the position shown to engagement Withthe bottom face of table 2l, thus reducing the depth of the recess into which the tube wall is drawn, and adapting the apparatus for operation upon inner tubes of different wall thickness.

The mechanism'for aperturing the inner tube 20 is carried by the frame II and comprises a verticallydisposed quill 34 that is slidingly mounted for axial movement in the forward overhanging portion of said frame. The outside surface of the quill is formed, on its rear side, with rack teeth 35, and meshed with the latter is an idler pinion 36, Figure 2, which in turn is meshed with an idler gear 3I of slightly larger size, said pinion and gear being journaled onsuitable stub shafts c'a'rried by the frame I'I. Meshed with gear 3'I is a horizontally disposed rack 38 that is slidably carriedby a bracket 39 secured to the side of frame I'I, said rackfbeing connected at its rear win be expninea' onthetopfaceioffthefbidcli 1n end to the piston rod of a fluid pressure operated cylinder 4l) that is mounted upon a lateral sur-4 face of said frame. The cylinder 40 is of the doubleacting type, the arrangement being such that the alternate charging of opposite ends thereof r'eciprocates the rack 38, with the result that the quill 34 is alternately raised and lowered. At its lower end the quill hasv a portion 34a of somewhat'larger diameter, and partly telescoped therewith is a'tubular head or cup 42 that is secured thereto'by 'set screws 43. At the upper end of the bore in head 42 is a bearing 44, and a similar bearing 45 is mounted within the upper end of quill 34, there being a vertically disposed punch spindle 46 carried by said bearings. The spindle 46 is of somewhat larger diameter below the bearing 44,V and above said bearing the spindle carries a collar'4'I, -the arrangement being such as to preclude axial movement of the spindle relatively of the'quill. vThe lower end portion of the spindle 46 'is still further enlarged in diameter, and is formed with an angular bore 48"therein that extendsaxially of vthe'enla-rged v`'end offthe spindle at its lower endan'd 'radially fthereof atit'supperf end,4 -tlie latter opening lonto the ou'ter `vface ofthe spindle abovey the lowermost 1 enlarged portion' thereof.- 1 On the bottom f'facef'ofthe spindle'the bore-48 is counterbored to receive la'tubularpunch or cutter^49 lthat is retained therein by a set screw 59.- As shown in Figuresfland-5 vthe inside diameter ofthe cutter 49r is somewhat res-tricted Vat `its'upper end' to prevent a slugfor blank cut from the inner tube from being drawn therethrough'.` Circumscribing the lower l'end portion-of the spindle 45 l-isa 4stripper member 5| that is partly enclosed withinv the lower-end portion'of the head 42, a portion-of nthestripperprojecting below the latter. Near-its upper end the stripper 5| is formed exteriorly with a 'circumferential shoul- Vderlupon 'which is seated a vcompression spring 52, the upperf end of said springjbearing against an internal shoulder formedin the bore of head 42,l thearrang'ementy being such as normally to urge the stripper'downwardly, relatively of 'fthe spindle 46 and head1 42.- Secured to the bottom of the head 42is' aretainer ring-53 thatunderliesa shoulderoffthe medial portion 'of the "stripper-l member and thereby retains the stripper 5| wit-hin the head 42. -A-setscrew 54 is threaded through the stripper'v5l` -within the head 42 and extends into an axially extending slot 55' in the perimeter of the'v stripper'member to prevent rotary movement thereof.' There is a slight clearance'between the lowermost' enlarged portion' of the rspindle y46 andthe inner circumference of the'stripper member 5|', and aV ring gasket 56 is `so mounted between-said members as to prevent Vthe'passage of air'therebetween.l

AThe lower end portion of the stripper 5| comprises 'apair of downwardly extending arms 5|a, v5l a disposed at 'diametrically opposite points of the stripper, the lower ends'of said arms being united to a flat stripper ring 58 that-is disposed in a horizontal plane, concentric'with the axis of over thebubble or blister inthe tube indicatedl by the numeral 59, Figures 3k and 4, and by pressing the vtwo plies together under the ring, reduce' the circumference of the blister and put that portion of the upper tube-wall plywithin the ring underv slight 'tension As downward movement of the stripper ring ceasesbecause of the resistance of the work therebeneath, continued downward movement of the head 42 and spindle 46, against the force of spring 52, moves the cutter 49 into engagement with'the upper tube-wall ply,v and through the latter, cutting a cylindrical blank or slug v60 therefrom, which slug is drawn upwardly into the cutter by suction, as .presentlywill be explained. Because of the-presence' ofthe recess or reentrant in the bottom ply of the tube 20; caused by the" suction appliedy thereto throughtduct25, there isA no possibility of the cutter 49 inflicting damage on'the said bottom ply; and presence of the bubble orl blister inthe ytube makes it unnecessary for the cutter to descend as far as otherwise would be necessary. The cutting of the slug is faciiltated 'y they slight tension, vvthat 4 region of the tube from which the slugis cut.r v

During the i cutting operation described, the

cutter 49 is rapidly-rotated*uponl its axis, and to this endthe spindle 46-is provided at its upper end,fabove bearing 45, -with a grooved pulley'v62 about which istrained an endless transmission belt'63, the latterA also being trainedabo'ut a grooved driving pulley- 64 mounted upon the shaft l65 of a motor 66. Said motor is mounted upon a suitable supporting bracket 61 thatis carried by the frame Il, at the rear thereof.-

- VAs previously stated, the slug 69 is drawn into the rotating cutter 49 by suction, and subsequent# ly it is ejected therefrom by super-atmospheric pressure. To this end thestripper member 5| is formed with a radial bore`69, and-the head 42 `is formedwith a radial bore 19, the latter being threaded to receive a flexible pipe 1|. Although the bores 69,10 are disposed inthe same vertical plane, they are not in vaxial alignment. AThe bore 69 functionschiefly as a means for applying suction Vvto the work, through the cutter 49, during the cutting operation, as a means for drawing the slug 60 up into the cutter. r4During the cutting operation, as shown in Figure 5 the stripper member- 5 Ilis moved upwardly relatively ofthe spindle 46'andrhead 42` to such an extent as substantial'- yly to shut off ythe space between the head and the top ofthe stripper, but at such a time a portion at least of the bore 69 is abovethe shoulder on'the spindle formed'by the lowermost portion of greater diameter, with the result that said bore is accessible to `air drawn through the bore 48 of the spindle. After a cutting operationg when the spindle and quill have been liftedr to the position shown in Figure 4, the stripperv 5| is in its lowered position under impetus of the spring 52 as shown, with the result that the stripper does not obstruct the bore 1D and air may flow readily between the pipe 'H and bore-48 of the spindle'.` Thus superatmospheric pressure discharged into the head 42 from pipe 1| 'is avail! able for ejecting a slug -60 that previouslyy has been drawn into the cutter 4'9.

Theaejecting of the slug is eiected automatically when the table 2| is swung angularly to its alternative position wherein the inner 4tube 29 is properly positioned beneath the valve-stem applying mechanism for the application of a valve stemxthereto. The ejectedvslug is received Yin a suitable receptacle or box 'l5 that is mounted upon a bracket 16 that is secured to thej table 2|, at the. rear thereof, the receptacle being so positioned upon the tableas to be disposed directly beneath the cutter 49 whenthe table is swung tor its alternative position beneath the valve-stem applying mechanism. The receptacle 15 is provided with a top closure in which 'is formed a countersunk aperture 11, Figurev 2i throughl which the slug enters the receptacle. The'receptacle is emptied from time to time as the slugs accumulate. l

,To facilitate the aperturing ofthe tube 20 by the vcutter 49, a liquid lubricant is applied to the latter immediately before it enters the work. Such lubricant requires to be highly volatile since the presence of moisture on the tube where the valve stem is applied thereto 'will result in a blister in the finished tube. Alcohol has been -found to be a satisfactoryv lubricant, although other highly volatile liquids may be found equally desirable. Alcohol is sprayed onto the rotating cutter 49 by meansrof a nozzle 19 that-issn positioned as to direct the spray above the stripper ring 58 and between the two arms 5|a that support' the same. The` nozzleV constitutes a part ofan atomizer comprising a reservoir `8| for the liquid, the ratcmizer being operated by means of a Vblast of air supplied thereto bymeans of the pipe line 82. The latter extends to a source of superatmospheric pressuremot shown), and includes therein a pressure regulator 83, pressure gauge 84, and a solenoid operated Valve 8,5` that operates automatically when other Aelements of the apparatus are in determinate positions.

The mechanism for applying a valve ,stem to the inner tube 20, over the aperture cut .therein by the cutter 49, is similar inl some respects to the aperture. forming mechanism. Thus it comprises a vertically disposed spindle-88 that is slidably mounted for axial movement in the overhanging portion of frame I8, ,parallelto the quill 34. The outer surface ofthe spindle is formed on its rear side, with rack teeth v89, and meshed with the latter is an idler pinion 90 which in turn is meshed with an idler gear 9| of slightly larger size, said .pinion and gear` being journaled on suitable stub shafts carried by the frame |8 and projecting laterally therefrom. Meshed with gear 9| is a horizontally disposed rack 92 that is slidably carried by a bracket 93 secured to the side of frame |8, said rack being connected at its rear-end to the'piston rod 94 of a double acting fluid pressure operated cylinder 95 that is mounted upon a lateral face of said frame by means of brackets 96, 99. The arrangement is such that the spindle 88 may be raised and lowered in the same manner as the quill 34 previously described, and such raising and lower- `ing is eiected automatically when other elements of the apparatus are in determinate positions, Secured to the lower end of spindle 88 is a tubular holder 91 Yfor receiving a rubber valve stem, with the baseflange of the latter disposed at the bottom thereof. Suitable leaf springs (not shown) are mounted in the holder 91 for lightly engaging the valve stem with suiiicient pressure to retain it in the holder against the forceiof gravity, yet enabling the valvestem readily to be withdrawn from the holder after thevalve stem base flange has been adhered to the inner tube 20, andthe holder 91 is lifted therefrom.

In Figure 3 a. rubber valve stem 99, such as is applied to the tube 20, is shown below the holder 91 forpurpose of illustration, it being understood that said valve stem will be mounted in the holder` with only its base flange exposed `at the bcttomgthereof at the beginningnof a. cycle of operation of the apparatus.

For greater assurance that alcohol lubricant, which may be on the tube 20 around the aperture therein, will be dried before the valve stem 99 is applied ,to the tube, Van air blast is directed against -the region of the tube that includes said aperture. To this end a. pipe line |0| Vconducting* air yunder super-atmospheric pressure has its delivery end provided with an arcuate nozzle |02 that is disposed adjacent the valve-stem applying mechanism, and so arranged as to direct a current of air'onto the apertured region of the tube20 on table 2|, when the llatter has been swung angularly to bring the aperture in the tube into axial alignment with `the spindle 88. For .releasing air from the pipe line |0I, the

latter is provided with a valve |03 having an operating plunger thatV projects into the arc `of movement ofthe arm 22, and is depressed by the latter when swung Ato 4position beneath the Yvalve stem. applyingvmechanism to release the air to the nozzle |02.

of theapparatus -operate automatically whenother mechanisms are determinately positioned. This is effected by means of certain, electrical switches, valves that are solenoid' operated for determinate time intervals and otherwise, and piping connections. Sincesaid mechanisms do not constitute a part vof the invention, most of them are omitted from the drawings and description to conserve time. However, a brief outline of their arrangement is Vgiven in order that the operation of` the apparatus` may -be understood.

As shown in Figure 1, there is provided a 3- way reverse acting diaphragm valve |04 towhich extends the flexiblepipe 1| that alternately applies suction to the head 42 and discharges air under super-atmospheric pressure thereinto. Extending from the valve |04 to a suitable source of suction (not shown) is a pipe |05, and connected to the latter is aflexible hose |06 that connects with the hose 26 that extends to table 2| for applying suction through the aperture 3| inthe top of the latter. vAlso connecting with the valve |04 is a pipe |01 that extends therefrom to a suitable source of air under pressurefnot shown). The valve |04 operates to apply suction through the pipe |06 and 1|, or to apply air under pressure through the latter pipe, accorde ing to the presence or absence of pressure in a pim |08 that connects with the top of the valve. The pipe |08 also is connected to a pipe (not shown) that supplies air under pressure to the rear end of cylinder 95 for charging the latter to project rack 92 and thereby to lower spindle 88, and thereby to apply a valve stem 99 to inner tube 20. Both the cylinder 95 and the t, cylinder are operated by suitable valves (not shown) which valves are solenoid operated, and include timing mechanism for controlling the length of time that the pistons thereof remain in outermost or projected positions. Operation i of said solenoids, and the solenoidA valve 85, is

.I controlled by means of two, normally open electrcal switches ||0 and which switches are mounted below the frames |1, I 8 so as alternately to be engaged by the arm 22 and closed, .as said arm is swung from one of `its angular positions to the other. A manually operated electrical switch ||2, in series with the aforesaid switches, is provided for effecting operation of the aperturing mechanism and the valve stem applying mechanism. y

, In the operation of the apparatus, the operator after stroking the endless tube structure 20 to form a blister 59 therein, cleans the top surface of the blister with a volatile liquid, and then mounts the tube on the table v2|as shown in Figure 3, with the cleaned surface uppermost and with the blister over the aperture 3| of the table. Suction through aperture 3| in said table draws a local region of the underlying tube. wall downwardly thereinto and forms a recess or depression therein as shown in Figure 5. Suction .IAs previouslyv stated, some of the. mechanisms also is applied to the head 42 through pipe 1|. Previously a valve stem 99 has been mounted in the holder 91, and the motor 66 is..constantly drivento rotate the cutter 49. The` operator then swings the table 2| to the left to align it properly with the aperturing mechanism, vwhich movement of the arm 22 also closesfthe control switch ||0, after which the operator presses the manually operated switch 2.v As soon as the latter switch is closed the solenoid operated valve is operated to admit air-tothe pipe .82 and thereby to cause a spray of alcoholto 'be dischargedfrom-the nozzle 19onto` the" cutter "49.

Closing of the last mentioned switch also eiects.

operation of the solenoid-operated valve that controls fluid pressure cylinder 40, the rear end of the latter thereby being charged as its front end is discharged, with the result that its piston is moved outwardly and the quill 34 moved downwardly. At the limit of the downward movement oi the quill, stripper ring 58 presses blister 59 of the Work and puts a portion of the blister wall under tension, and said tensioned portion then is apertured by the rotating cutter 49. Thev slug 50 cut out by the cutter is drawn up into the latter by the suction within the head 42. As soon as the quill 34 reaches its lowermost position the time operated solenoid valve controlling cylinder 40 reverses its position to effect the lifting of the quill, at which time the stripper ring 58 operates to strip the tube wall from the cutter 49. n

The operator then swings the table 2| to the right to bring the apertured tube thereon beneath the valve stem applying mechanism,. and to position the receptacle 'l5 carried thereby beneath the aperturing mechanism with its'aperture 'I1 directly below the cutter 49. As table 2| is swung to its alternative position, its supporting arm 22 engages the operating plunger of valve |03 to open the latter and admit air under pressure to the nozzle |02, the latter directing the air onto the aperture previously formed in the inner tube and drying any lubricant remaining thereon. Swinging of arm 22 also opens the switch it previously 'had closed, and closes switch in the circuit of the other solenoid operated valve. erates the manually operated switch, thus starting a cycle of operation of said solenoid operated valve, which first effects the charging of the rear end of cylinder 95 to lower the spindle 88. Charging of said cylinder 95 also admits air through pipe |08 to valve |04, the latter then functioning to shut off suction to the head 42 and to admit air under pressure thereto, with the result that the slug 60 is ejected from the cutter '49 and projected into the receptacle 15. As the spindle 88 reaches its lowermost position it presses the base flange of the valve stem 99 upon the inner tube 20, over the aperture therein, so that said ilange adheres to the tube. The control valve of cylinder 95 automatically reverses itself to retract the piston of said cylinder and thereby to lift spindle 88, the valve stem 99 being thereby pulled from the holder 91 on the end of the spindle. Reversing of cylinder 95 releases the pressure in pipe |08 and thereby restores valve |04 to original position, with the result that air pressure to head 42 is shut 01T and suction substituted therefor. The inner tube with valve stem applied thereto is then removed from table 2| and dropped onto conveyor I, which removes it from the apparatus to a point removed therefrom where other operations may be performed upon it. This completes a cycle of operation, which may be repeated as often as desired.

The invention is simple and eilicient, and assures that the aperturing of the tube wall will not result in damage to the opposite wall-of the tube.

The operator then again op- Modification may be resorted to without departing from the spirit of the invention, or the'y combination of a tube aperturing mechanism and a valve-stem applying mechanism spaced therefrom, a support for the'work alternatively positionable below the aperturing mechanism and the valve stem applying mechanism, means for applying suction to the aperturing mechanism when the work support is beneath the same, and means for applying superatmospheric pressure to the aperturing mechanism when the work support it beneath the valve stern applying mechanism.

2. A combination as defined in claim 1 including a receptacle carried by the work support and so arranged thereonl as to be positioned beneath the aperturing mechanism when the work support is beneath the valve stem applying mechanism, said receptacle receiving a slug ejected from the aperturing mechanism when superatmospheric pressure is applied thereto.

3. In apparatus for making inner tubes, the combination of a vertically reciprocable head, a rotatable spindle disposed within the same coaXially thereof, a circular cutter at the lower end of said spindle, stripper mechanism carried by said head and movable axially relatively of the head and said cutter, said stripper mechanism comprising a flat ring disposed concentrioally of the cuttenmeans for applying superatmospheric pressure around the upper end of the stripper structure to the interior of the cutter in one of the positions of the stripper, and means for applying suction through the upper portion of the stripperstructure to the interior of the cutter in the alternative position of the stripper.

4. In apparatus for making inner tubes, the combination of a tubular rotary cutter, a worksupporting table selectively positionable in either of two alternative positions, in one of which positions it is directly beneath said cutter, means for reciprocating the cutter toward and from an inner tube on said table, means for applying suction or super-atmospheric pressure alternatively to the cutter, respective means controlling the application of suction and super-atmospheric pressure to said cutter, and means for operating said last mentioned means automatically according to the position of the table.

5. In apparatus for making inner tubes, the combination of a tubular'rotary cutter, a worksupporting table selectively positionable in either of two alternativepositions, in one of which positions it is directly beneath said cutter, a swingable arm supporting said table, means for reciprocating said cutter toward and from an inner tube on said table, means for applying suction or super-atmospheric pressure alternatively to the cutter, and respective means controlling the application of suction and superatmospheric pressure to said cutter, said means positioned in the path of the swingable arm so as Vtobe operated by the swinging thereof.

HORACE D. STEVENS. 

